<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@page import="cn.itcast.Person"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <title>jstl+el表达式示例代码</title>
  </head>
  
  <body>
    
    
    <!-- 使用jstl+el表达式可以迭代list集合 -->
    <% 
    	Person p1 = new Person();
    	p1.setName("aa111");
    	
    	Person p2 = new Person();
    	p2.setName("bb");
    	
    	List list = new ArrayList();
    	list.add(p1);
    	list.add(p2);
    	
    	request.setAttribute("list",list);
    %>
    
    <c:forEach var="person" items="${list}">
    	${person.name }<br/>
    </c:forEach>
    
    
    <!-- 使用jstl+el表达式可以迭代map集合 -->
    <% 
    	Map map = new HashMap();
    	map.put("a","aaaaxxx");
    	map.put("b","bbbb");
    	map.put("c","cccc");
    	map.put("1","aaaa1111");
    	
    	request.setAttribute("map",map);
    %>
    
    <br/>
    
   	<%-- Set<Map.Entry> set = map.entrySet()--%>
    <c:forEach var="me" items="${map}">  
    	${me.key } = ${me.value }<br/>
    </c:forEach>
    
    
    <br/><br/>
    
    <c:if test="${user!=null}">
    	欢迎您：${user.uesrname }
    </c:if>
    
     <c:if test="${user==null}">
    	用户名：<input type="text" name="username">
    	密码：<input type="password" name="password">
    	<input type="submit" value="登陆">
    </c:if>
    
    
    
  </body>
</html>
